fs/reiser4/forward.h

   1 /* Copyright 2001, 2002, 2003 by Hans Reiser, licensing governed by
   2    reiser4/README */
   3
   4 /* Forward declarations. Thank you Kernighan. */
   5
   6 #if !defined(__REISER4_FORWARD_H__)
   7 #define __REISER4_FORWARD_H__
   8
   9 #include <asm/errno.h>
  10 #include <linux/types.h>
  11
  12 typedef struct zlock zlock;
  13 typedef struct lock_stack lock_stack;
  14 typedef struct lock_handle lock_handle;
  15 typedef struct znode znode;
  16 typedef struct flow flow_t;
  17 typedef struct coord coord_t;
  18 typedef struct tree_access_pointer tap_t;
  19 typedef struct reiser4_object_create_data reiser4_object_create_data;
  20 typedef union reiser4_plugin reiser4_plugin;
  21 typedef __u16 reiser4_plugin_id;
  22 typedef __u64 reiser4_plugin_groups;
  23 typedef struct item_plugin item_plugin;
  24 typedef struct jnode_plugin jnode_plugin;
  25 typedef struct reiser4_item_data reiser4_item_data;
  26 typedef union reiser4_key reiser4_key;
  27 typedef struct reiser4_tree reiser4_tree;
  28 typedef struct carry_cut_data carry_cut_data;
  29 typedef struct carry_kill_data carry_kill_data;
  30 typedef struct carry_tree_op carry_tree_op;
  31 typedef struct carry_tree_node carry_tree_node;
  32 typedef struct carry_plugin_info carry_plugin_info;
  33 typedef struct reiser4_journal reiser4_journal;
  34 typedef struct txn_atom txn_atom;
  35 typedef struct txn_handle txn_handle;
  36 typedef struct txn_mgr txn_mgr;
  37 typedef struct reiser4_dir_entry_desc reiser4_dir_entry_desc;
  38 typedef struct reiser4_context reiser4_context;
  39 typedef struct carry_level carry_level;
  40 typedef struct blocknr_set_entry blocknr_set_entry;
  41 /* super_block->s_fs_info points to this */
  42 typedef struct reiser4_super_info_data reiser4_super_info_data;
  43 /* next two objects are fields of reiser4_super_info_data */
  44 typedef struct reiser4_oid_allocator reiser4_oid_allocator;
  45 typedef struct reiser4_space_allocator reiser4_space_allocator;
  46
  47 typedef struct flush_scan flush_scan;
  48 typedef struct flush_position flush_pos_t;
  49
  50 typedef unsigned short pos_in_node_t;
  51 #define MAX_POS_IN_NODE 65535
  52
  53 typedef struct jnode jnode;
  54 typedef struct reiser4_blocknr_hint reiser4_blocknr_hint;
  55
  56 typedef struct uf_coord uf_coord_t;
  57 typedef struct hint hint_t;
  58
  59 typedef struct ktxnmgrd_context ktxnmgrd_context;
  60
  61 struct inode;
  62 struct page;
  63 struct file;
  64 struct dentry;
  65 struct super_block;
  66
  67 /* return values of coord_by_key(). cbk == coord_by_key */
  68 typedef enum {
  69         CBK_COORD_FOUND = 0,
  70         CBK_COORD_NOTFOUND = -ENOENT,
  71 } lookup_result;
  72
  73 /* results of lookup with directory file */
  74 typedef enum {
  75         FILE_NAME_FOUND = 0,
  76         FILE_NAME_NOTFOUND = -ENOENT,
  77         FILE_IO_ERROR = -EIO,   /* FIXME: it seems silly to have special OOM,
  78                                    IO_ERROR return codes for each search. */
  79         FILE_OOM = -ENOMEM      /* FIXME: it seems silly to have special OOM,
  80                                    IO_ERROR return codes for each search. */
  81 } file_lookup_result;
  82
  83 /* behaviors of lookup. If coord we are looking for is actually in a tree,
  84     both coincide. */
  85 typedef enum {
  86         /* search exactly for the coord with key given */
  87         FIND_EXACT,
  88         /* search for coord with the maximal key not greater than one
  89            given */
  90         FIND_MAX_NOT_MORE_THAN  /*LEFT_SLANT_BIAS */
  91 } lookup_bias;
  92
  93 typedef enum {
  94         /* number of leaf level of the tree
  95            The fake root has (tree_level=0). */
  96         LEAF_LEVEL = 1,
  97
  98         /* number of level one above leaf level of the tree.
  99
 100            It is supposed that internal tree used by reiser4 to store file
 101            system data and meta data will have height 2 initially (when
 102            created by mkfs).
 103          */
 104         TWIG_LEVEL = 2,
 105 } tree_level;
 106
 107 /* The "real" maximum ztree height is the 0-origin size of any per-level
 108    array, since the zero'th level is not used. */
 109 #define REAL_MAX_ZTREE_HEIGHT     (REISER4_MAX_ZTREE_HEIGHT-LEAF_LEVEL)
 110
 111 /* enumeration of possible mutual position of item and coord.  This enum is
 112     return type of ->is_in_item() item plugin method which see. */
 113 typedef enum {
 114         /* coord is on the left of an item */
 115         IP_ON_THE_LEFT,
 116         /* coord is inside item */
 117         IP_INSIDE,
 118         /* coord is inside item, but to the right of the rightmost unit of
 119            this item */
 120         IP_RIGHT_EDGE,
 121         /* coord is on the right of an item */
 122         IP_ON_THE_RIGHT
 123 } interposition;
 124
 125 /* type of lock to acquire on znode before returning it to caller */
 126 typedef enum {
 127         ZNODE_NO_LOCK = 0,
 128         ZNODE_READ_LOCK = 1,
 129         ZNODE_WRITE_LOCK = 2,
 130 } znode_lock_mode;
 131
 132 /* type of lock request */
 133 typedef enum {
 134         ZNODE_LOCK_LOPRI = 0,
 135         ZNODE_LOCK_HIPRI = (1 << 0),
 136
 137         /* By setting the ZNODE_LOCK_NONBLOCK flag in a lock request the call to
 138            longterm_lock_znode will not sleep waiting for the lock to become
 139            available.  If the lock is unavailable, reiser4_znode_lock will
 140            immediately return the value -E_REPEAT. */
 141         ZNODE_LOCK_NONBLOCK = (1 << 1),
 142         /* An option for longterm_lock_znode which prevents atom fusion */
 143         ZNODE_LOCK_DONT_FUSE = (1 << 2)
 144 } znode_lock_request;
 145
 146 typedef enum { READ_OP = 0, WRITE_OP = 1 } rw_op;
 147
 148 /* used to specify direction of shift. These must be -1 and 1 */
 149 typedef enum {
 150         SHIFT_LEFT = 1,
 151         SHIFT_RIGHT = -1
 152 } shift_direction;
 153
 154 typedef enum {
 155         LEFT_SIDE,
 156         RIGHT_SIDE
 157 } sideof;
 158
 159 #define round_up(value, order)                                          \
 160         ((typeof(value))(((long) (value) + (order) - 1U) &      \
 161                              ~((order) - 1)))
 162
 163 /* values returned by squalloc_right_neighbor and its auxiliary functions */
 164 typedef enum {
 165         /* unit of internal item is moved */
 166         SUBTREE_MOVED = 0,
 167         /* nothing else can be squeezed into left neighbor */
 168         SQUEEZE_TARGET_FULL = 1,
 169         /* all content of node is squeezed into its left neighbor */
 170         SQUEEZE_SOURCE_EMPTY = 2,
 171         /* one more item is copied (this is only returned by
 172            allocate_and_copy_extent to squalloc_twig)) */
 173         SQUEEZE_CONTINUE = 3
 174 } squeeze_result;
 175
 176 /* Do not change items ids. If you do - there will be format change */
 177 typedef enum {
 178         STATIC_STAT_DATA_ID = 0x0,
 179         SIMPLE_DIR_ENTRY_ID = 0x1,
 180         COMPOUND_DIR_ID = 0x2,
 181         NODE_POINTER_ID = 0x3,
 182         EXTENT_POINTER_ID = 0x5,
 183         FORMATTING_ID = 0x6,
 184         CTAIL_ID = 0x7,
 185         BLACK_BOX_ID = 0x8,
 186         LAST_ITEM_ID = 0x9
 187 } item_id;
 188
 189 /* Flags passed to jnode_flush() to allow it to distinguish default settings
 190    based on whether commit() was called or VM memory pressure was applied. */
 191 typedef enum {
 192         /* submit flush queue to disk at jnode_flush completion */
 193         JNODE_FLUSH_WRITE_BLOCKS = 1,
 194
 195         /* flush is called for commit */
 196         JNODE_FLUSH_COMMIT = 2,
 197         /* not implemented */
 198         JNODE_FLUSH_MEMORY_FORMATTED = 4,
 199
 200         /* not implemented */
 201         JNODE_FLUSH_MEMORY_UNFORMATTED = 8,
 202 } jnode_flush_flags;
 203
 204 /* Flags to insert/paste carry operations. Currently they only used in
 205    flushing code, but in future, they can be used to optimize for repetitive
 206    accesses.  */
 207 typedef enum {
 208         /* carry is not allowed to shift data to the left when trying to find
 209            free space  */
 210         COPI_DONT_SHIFT_LEFT = (1 << 0),
 211         /* carry is not allowed to shift data to the right when trying to find
 212            free space  */
 213         COPI_DONT_SHIFT_RIGHT = (1 << 1),
 214         /* carry is not allowed to allocate new node(s) when trying to find
 215            free space */
 216         COPI_DONT_ALLOCATE = (1 << 2),
 217         /* try to load left neighbor if its not in a cache */
 218         COPI_LOAD_LEFT = (1 << 3),
 219         /* try to load right neighbor if its not in a cache */
 220         COPI_LOAD_RIGHT = (1 << 4),
 221         /* shift insertion point to the left neighbor */
 222         COPI_GO_LEFT = (1 << 5),
 223         /* shift insertion point to the right neighbor */
 224         COPI_GO_RIGHT = (1 << 6),
 225         /* try to step back into original node if insertion into new node
 226            fails after shifting data there. */
 227         COPI_STEP_BACK = (1 << 7)
 228 } cop_insert_flag;
 229
 230 typedef enum {
 231         SAFE_UNLINK,            /* safe-link for unlink */
 232         SAFE_TRUNCATE           /* safe-link for truncate */
 233 } reiser4_safe_link_t;
 234
 235 /* this is to show on which list of atom jnode is */
 236 typedef enum {
 237         NOT_CAPTURED,
 238         DIRTY_LIST,
 239         CLEAN_LIST,
 240         FQ_LIST,
 241         WB_LIST,
 242         OVRWR_LIST
 243 } atom_list;
 244
 245 /* __REISER4_FORWARD_H__ */
 246 #endif
 247
 248 /* Make Linus happy.
 249    Local variables:
 250    c-indentation-style: "K&R"
 251    mode-name: "LC"
 252    c-basic-offset: 8
 253    tab-width: 8
 254    fill-column: 120
 255    End:
 256 */